U.S. patent application number 10/197672 was filed with the patent office on 2003-08-21 for apparatus and method of recovering reactive power of plasma display panel.
This patent application is currently assigned to SAMSUNG ELECTRONICS CO., LTD.. Invention is credited to Kang, Chun-Seong.
Application Number | 20030156081 10/197672 |
Document ID | / |
Family ID | 27725781 |
Filed Date | 2003-08-21 |
United States Patent
Application |
20030156081 |
Kind Code |
A1 |
Kang, Chun-Seong |
August 21, 2003 |
Apparatus and method of recovering reactive power of plasma display
panel
Abstract
An apparatus to recover a reactive power of a plasma display
panel, the apparatus including a power supply source, first and
second discharge electrodes to perform a surface discharge with a
voltage from the power supply source, a panel capacitor having
opposite ends connected to the respective discharge electrodes and
which is discharged by supplying a charge voltage to one of the
first and second discharge electrodes, an inductor provided between
the one of the first and second discharge electrodes and the panel
capacitor. The inductor is charged by a discharge current of the
panel capacitor and induces the charge voltage of the panel
capacitor to be recovered.
Inventors: |
Kang, Chun-Seong;
(Suwon-city, KR) |
Correspondence
Address: |
STAAS & HALSEY LLP
SUITE 700
1201 NEW YORK AVENUE, N.W.
WASHINGTON
DC
20005
US
|
Assignee: |
SAMSUNG ELECTRONICS CO.,
LTD.
Suwon city
KR
|
Family ID: |
27725781 |
Appl. No.: |
10/197672 |
Filed: |
July 18, 2002 |
Current U.S.
Class: |
345/60 |
Current CPC
Class: |
G09G 2310/066 20130101;
G09G 3/2965 20130101 |
Class at
Publication: |
345/60 |
International
Class: |
G09G 003/28 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 19, 2002 |
KR |
2002-8786 |
Claims
What is claimed is:
1. A reactive power recovering circuit for use with a plasma
display panel including a power supply source and first and second
discharge electrodes disposed to perform a surface discharge with a
supply voltage from the power supply source, the circuit
comprising: a panel capacitor having opposite ends, each end being
connected to a corresponding one of the first and second discharge
electrodes, said panel capacitor being discharged by alternately
supplying a charge voltage to the first and second discharge
electrodes; switches to turn on or off a connection between said
panel capacitor, the first and second discharge electrodes, and the
power supply source; an inductor provided between said panel
capacitor and one of the first and second discharge electrodes,
said inductor being charged by a discharge current discharged by
said panel capacitor and to inductively store the charge voltage to
be recovered for use by said panel capacitor using the discharge
current; and a controller to control said switches so as to allow
the charge voltage of said panel capacitor to be alternately
supplied to the first and second discharge electrodes.
2. The reactive power recovering circuit according to claim 1,
wherein: one of said switches comprises a power connecting switch
to turn on or off the supply voltage supplied by the power supply
source to said panel capacitor, and another one of said switches
comprises a ground connecting switch to turn on or off a connection
between said panel capacitor with one of the first and second
discharge electrodes.
3. The reactive power recovering circuit according to claim 2,
further comprising a resistor connected in series to the power
connecting switch and which reduces an overshoot voltage.
4. The reactive power recovering circuit according to claim 3,
wherein said switches comprise field effective transistors
(FETs).
5. A method of recovering reactive power of a plasma display panel
including a power supply source, a panel capacitor charged with a
supply voltage from the power supply source, first and second
discharge electrodes performing a surface discharge according to
charge/discharge of the panel capacitor, switches to
charge/discharge the panel capacitor, and an inductor connected in
series to the panel capacitor, the method comprising: charging the
panel capacitor; discharging the panel capacitor and charging the
inductor with a discharged current from the panel capacitor;
forming a first electric current path from the inductor to the
panel capacitor and charging the panel capacitor with a charged
energy of the inductor; and forming a second electric current path
in a reverse direction of the first electric current path and
discharging the charged energy from the panel capacitor.
6. The method according to claim 5, wherein said charging the panel
capacitor by the inductor further comprises supplementing
insufficient voltage of the panel capacitor with the voltage
supplied from the power supply source to achieve a desired voltage
level for discharge.
7. The method according to claim 5, wherein: one of the switches
comprises a power connecting switch to turn on or off the voltage
supplied from the power supply source to the panel capacitor, and
another of the switches comprises a ground connecting switch to
turn on or off a connection between the panel capacitor and one of
the first and second discharge electrodes.
8. The method according to claim 7, further comprising reducing an
overshoot voltage using a resistor connected in series to the power
connecting switch.
9. The method according to claim 8, wherein the switches comprise
field effective transistors (FETs).
10. The reactive power recovering circuit according to claim 1,
wherein said inductor is charged both when said panel capacitor
charges the first discharge electrode and when said panel capacitor
charges the second discharge electrode.
11. The reactive power recovering circuit according to claim 10,
wherein: said inductor is charged using a first discharge current
from said panel capacitor to the first discharge electrode when
said panel capacitor supplies the charge voltage to the first
discharge electrode, and said inductor is also charged using a
second discharge current from said panel capacitor to the second
discharge electrode when said panel capacitor supplies the charge
voltage to the second discharge electrode.
12. The reactive power recovering circuit according to claim 1,
wherein said inductor charges said panel capacitor after said panel
capacitor is discharged after charging the first discharge
electrode and after said panel capacitor is discharged after
charging the second discharge electrode.
13. The method according to claim 5, further comprising again
charging the inductor during said forming the second electric
current path.
14. The method according to claim 5, wherein said discharging the
panel capacitor and charging the inductor comprises forming a third
electric current path in a same direction as the first electric
current path, discharging the panel capacitor, and charging the
inductor.
15. A plasma display panel, comprising: a front substrate; first
and second discharge electrodes disposed along a first direction on
a bottom surface of said front substrate; a first dielectric layer
on the bottom surface of said front substrate to cover said first
and second discharge electrodes; a rear substrate opposite to and
facing said front substrate; address electrodes on a top surface of
said rear substrate, said address electrodes being disposed in a
second direction non-parallel with the first direction of said
first and second discharge electrodes; a second dielectric layer on
said rear substrate to cover said address electrodes; partitions to
partition a discharge space under said first dielectric layer, said
partitions being on said second dielectric layer; phosphor layers
formed on inner walls of said partitions; a power supply source to
supply a supply voltage for use in performing a surface discharge
using said first and second discharge electrodes; and a reactive
power recovering circuit comprising: a panel capacitor having
opposite ends, each end being connected to a corresponding one of
said first and second discharge electrodes, the panel capacitor
being discharged by alternately supplying a charge voltage to said
first and second discharge electrodes, and an energy storage device
provided between the panel capacitor and one of said first and
second discharge electrodes, the energy storage device being
charged by a discharge current from the panel capacitor and to
store the charge voltage to be recovered for use by the panel
capacitor using the discharge current.
16. The plasma display panel according to claim 15, wherein: the
energy storage device comprises an inductor, and said reactive
power recovering circuit further comprises: switches to turn on or
off a connection between the panel capacitor, said first and second
discharge electrodes, and said power supply source, and a
controller to control the switches so as to allow the charge
voltage of the panel capacitor to be alternately supplied to said
first and second discharge electrodes.
17. The plasma display panel according to claim 16, wherein: one of
the switches comprises a power connecting switch to turn on or off
the supply voltage supplied by said power supply source to the
panel capacitor, and another one of the switches comprises a ground
connecting switch to turn on or off a connection between the panel
capacitor with one of said first and second discharge
electrodes.
18. The plasma display panel according to claim 17, wherein said
reactive power recovering circuit further comprises a resistor
connected in series to the power connecting switch in order to
reduce an overshoot voltage.
19. The plasma display panel according to claim 18, wherein the
switches comprise field effective transistors (FETs).
20. The plasma display panel according to claim 15, wherein the
energy storage device is charged when the panel capacitor
discharges so as to charge said first discharge electrode and when
the panel capacitor discharges so as to charge said second
discharge electrode.
21. The plasma display panel according to claim 15, wherein the
energy storage device stores energy using a magnetic field when the
panel capacitor discharges so as to charge said first discharge
electrode and when the panel capacitor discharges so as to charge
said second discharge electrode.
22. The plasma display panel according to claim 15, wherein said
reactive power recovering circuit further comprises: a first
discharge electrode driving unit connected between said power
supply source, the panel capacitor, and said first discharge
electrode, a second discharge electrode driving unit connected
between said power supply source, the panel capacitor, and said
second discharge electrode, and the energy storage device is
connected in series with the panel capacitor between the first and
second discharge electrode driving units.
23. The plasma display panel according to claim 22, wherein: the
energy storage device is connected between the panel capacitor and
a node, and the node connects said power supply source and one of
said first and second discharge electrodes.
24. The plasma display panel according to claim 22, wherein the
energy storage device is charged when a current path is formed
between said second discharge electrode, the panel capacitor, and
the supply voltage provided by said power supply source through the
first discharge electrode driving unit.
25. The plasma display panel according to claim 22, wherein the
energy storage device is charged when a current path is formed
between said first discharge electrode, the panel capacitor, and
the supply voltage provided by said power supply source through the
second discharge electrode driving unit.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of Korean Application
No. 2002-8786, filed Feb. 19, 2002, in the Korean Intellectual
Property Office, the disclosure of which is incorporated herein by
reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates in general to a plasma display
apparatus which displays images thereon by use of an electric
discharge, and more particularly, to a plasma display panel
(hereinafter, a "PDP") having a circuit to recover reactive
power.
[0004] 2. Description of the Related Art
[0005] A PDP is an apparatus that allows pictures to be displayed
thereon using a gas discharge. Depending upon types of methods used
to drive the PDP, the PDP is largely categorized into a direct
current (DC) type PDP, which performs a facing discharge, and an
alternating current (AC) type PDP, which performs a surface
discharge. The AC type PDP is more advantageous since it has a
lower power consumption and a longer lifetime in comparison with
the DC type. For this reason, the AC type PDP has lately attracted
considerable attention.
[0006] The PDP using the AC driving type applies an alternating
current (AC) voltage between electrodes insulated with a dielectric
layer, and performs a discharge every half-cycle of the AC voltage.
The AC type PDP displays a picture mainly in a sub-field method. In
the sub-field method, since the power consumption used to charge
and discharge of the PDP panel during a sustain of the discharge is
very large, a circuit is used in a driving device of the PDP to
recover reactive power.
[0007] Generally, the reactive power recovering circuit includes a
scanning/sustaining electrode unit that drives cells connected to a
Y-electrode (hereinafter, "Y-electrode unit driving cell" 20) and a
common electrode unit that drives cells commonly connected to a
plurality of X-electrodes (hereinafter, "X-electrode unit driving
cell" 30). As shown in FIG. 4, adjacent pairs of the Y-electrodes
and the X-electrodes are arrayed in sustaining electrode pairs. The
sustaining electrode pairs perform a surface discharge using
sustain pulses generated in the Y-electrode unit driving cell 20
and the X-electrode unit driving cell 30. By these pulses, a
brightness of the picture displayed on a screen is sustained. A
panel capacitor 39 indicates an electrostatic capacity formed
between the Y-electrode and the X-electrode in the panel in an
equivalent manner.
[0008] The Y-electrode unit driving cell 20 includes first and
second switches 31 and 33 connected in series between an outside
sustaining voltage supply source (Vcc) and a ground (i.e., the
Y-electrode), an outside capacitor 43a provided in parallel
relative to the second switch 33, third and fourth switches 35 and
37 provided between the outside capacitor 43a and a first node n1,
and a coil 41 connected between the first node n1 and a second node
n2. The X-electrode unit driving cell 20 is constructed
symmetrically to the Y-electrode unit driving cell 20, with the
panel capacitor 39 being in the center therebetween. The
X-electrode unit driving cell 30 includes fifth and sixth switches
Xs and Xg corresponding to the first and second switches 31 and 33,
seventh and eighth switches Xr and Xf corresponding to the third
and fourth switches 35 and 37, a coil Lx, and an outside capacitor
43b.
[0009] Hereinbelow, the operation of the reactive power recovering
circuit will be described, focusing on the Y-electrode unit driving
cell 20. The panel capacitor 39 is charged with voltage according
to the on/off states of each switch 31, 33, 35, 37, Xs, Xg, Xr, Xf
of the X and Y-electrode unit driving cells 20 and 30. The voltage
charged in the panel capacitor 39 is discharged at the period when
the second switch 33 is turned on. If the fourth switch 37 is
simultaneously turned on during the discharge of the panel
capacitor 39, the electric current flows into the outside capacitor
43a, thereby allowing energy to be absorbed thereinto. Then, if the
third switch 35 is turned on, the energy absorbed into the outside
capacitor 43a is recovered by passing through the coil 41, and the
panel capacitor 39 is charged again with the energy. Thereafter,
the energy is used in a next switching process.
[0010] At this time, to supplement insufficient voltage of the
panel capacitor 39, the first switch 31 is turned on. The voltage
charged in the panel capacitor 39 is discharged depending on the
on/off state of each switch Xs, Xg, Xr, Xf within the X-electrode
unit driving cell 30, as in the switching process of the
Y-electrode unit driving cell 20. Through these processes described
above, the X-electrode unit driving cell 30 alternately charges and
discharges the panel capacitor 39 with the Y-electrode unit driving
cell 20. As a result, the sustaining discharge is available by
charging/discharging the panel capacitor 39 by use of the outside
capacitors 43a, 43b, which respectively function as a voltage
source.
[0011] However, in the conventional reactive power recovering
circuit, the construction of the circuit for recovering the energy
itself has been very complicated. In addition, the amount of power
consumed by each switching device and each diode, to which a
plurality of switching devices and a diode to prevent a reverse
flow are connected in series, has been large.
SUMMARY OF THE INVENTION
[0012] The present invention has been made keeping in mind the
above and other problems and shortcomings, and an object of the
present invention is to provide a plasma display panel having a
reactive power recovering circuit simplified in structure, wherein
power consumption is reduced, and a method of controlling the
same.
[0013] Additional objects and advantages of the invention will be
set forth in part in the description which follows and, in part,
will be obvious from the description, or may be learned by practice
of the invention.
[0014] This and other objects of the present invention may be
achieved by providing a plasma display panel according to an
embodiment of the invention comprising a power supply source to
provide a supply voltage, first and second discharge electrodes to
perform a surface discharge with the supply voltage from the power
supply source, a panel capacitor whose opposite ends are connected
to the respective discharge electrodes, the panel capacitor being
discharged by supplying a charge voltage to either of the first
discharge electrode or the second discharge electrode, a plurality
of switches to turn on or off a connection of the panel capacitor
connected to the respective discharge electrodes and the power
supply source, an inductor provided between the panel capacitor and
one of the first and second discharge electrodes, the inductor
being charged by a discharge current discharged from the panel
capacitor and to inductively store the charge voltage to be
recovered for use by the panel capacitor, and a controller to
control the switches so as to allow the charge voltage of the panel
capacitor to be alternately supplied to the respective discharge
electrode.
[0015] According to an aspect of the invention, one of the switches
comprises a power connecting switch to turn on or off the supply
voltage from the power supply source to the panel capacitor, and
another one of the switches comprises a ground connecting switch to
turn on or off a connection of the panel capacitor with one of the
first and second discharge electrodes.
[0016] According to another aspect of the invention, the plasma
display panel further comprises a resistor connected in series to
the power connecting switch in order to reduce an overshoot
voltage.
[0017] According to yet another aspect of the invention, the
switches include field effective transistors (FETs).
[0018] According to another embodiment of the present invention, a
method of recovering a reactive power of a plasma display panel,
which includes a power supply source, a panel capacitor charged
with a supply voltage from the power supply source, first and
second discharge electrodes performing a surface discharge
according to charge/discharge of the panel capacitor, switches to
charge/discharge the panel capacitor, and an inductor connected in
series to the panel capacitor, the method comprising charging the
panel capacitor, discharging the panel capacitor and charging the
inductor with a discharged current, forming a first electric
current path from the inductor to the panel capacitor and charging
the panel capacitor with a charged energy of the inductor, and
forming a second electric current path in a reverse direction of
the first electric current path and discharging the panel
capacitor.
[0019] According to a further aspect of the invention, the charging
the panel capacitor by the inductor further comprises supplementing
insufficient voltage of the panel capacitor with the voltage
supplied from the power supply source.
[0020] According to a further aspect of the invention, one of the
switches includes a power connecting switch to turn on or off a
voltage supplied from the power supply source to the panel
capacitor, and another of the switches includes a ground connecting
switch to turn on or off a connection of the panel capacitor with
one of the first and second discharge electrodes.
[0021] According to a yet further aspect of the invention, a
resistor is connected in series to the power connecting switch,
thereby reducing overshoot voltage.
[0022] According to a still further aspect of the invention, the
switches include field effective transistors (FETs).
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The present invention will be better understood and its
various objects and advantages will be more fully appreciated from
the following description taken in conjunction with the
accompanying drawings, in which:
[0024] FIG. 1 is a block diagram of a reactive power recovering
circuit of a PDP according to an embodiment of the present
invention;
[0025] FIGS. 2A, 2B, 2C and 2D show current flows when a panel
capacitor of FIG. 1 is charged or discharged;
[0026] FIGS. 3A and 3B are views showing each voltage at both ends
of the panel capacitor of FIG. 1;
[0027] FIG. 4 is a circuit diagram for recovering a reactive power
of a conventional PDP; and
[0028] FIG. 5 is a perspective view of a plasma display panel
according to an embodiment of the invention.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0029] Hereinbelow, the present invention will be described in more
detail with reference to the accompanying drawings, wherein like
reference numerals refer to the like elements throughout. The
embodiments are described below in order to explain the present
invention by referring to the figures.
[0030] FIG. 1 is a block diagram of a reactive power recovering
circuit of a PDP according to an embodiment of the present
invention. As illustrated therein, a driving circuit driven to
generate an electric discharge in discharge sustaining electrode
pairs includes a Y-electrode unit driving cell 1 to drive the
Y-electrode of the discharge sustaining electrode pair. X-electrode
unit driving cells 3 drive the X-electrodes. A controller (not
shown) applies a control signal to drive the Y-electrode unit
driving cell 1 and the X-electrode unit driving cells 3. A panel
capacitor 9 indicates an equivalent capacitance formed between the
Y-electrode and the X-electrode in the panel.
[0031] The Y-electrode unit driving cell 1 includes first and
second switches 1a and 3a, which are provided between a power
supply source (Vcc) and a ground (i.e., the Y-electrode),
respectively. The first and second switches 1a and 3a are turned on
or off to charge or discharge the voltage of the panel capacitor 9.
A resistor 5a is connected in series to the first switch 1a.
[0032] The X-electrode unit driving cell 3 is structured
symmetrically as compared to the Y-electrode unit driving cell 1.
The panel capacitor 9 is disposed between the X-electrode unit
driving cell 3 and the Y-electrode unit driving cell 1. The
X-electrode unit driving cell 3 includes third and fourth switches
1b and 3b, which correspond to the first and second switches 1a and
3a, and a resistor 5b, which corresponds to the resistor 5a and
which is connected in series to the third switch 1b.
[0033] As shown, each resistor 5a and 5b functions to reduce an
overshoot of the voltage of the discharge pulse applied from the
first switch 1a or the second switch 1b, the first and second
switches 1a, 1b being individually turned on at the period during
which the panel capacitor 9 is charged using the voltage of the
power supply source Vcc. At this time, the controller outputs a
control signal to turn on or off each switch 1a, 3a, 1b, 3b so as
to generate the charge/discharge in the panel capacitor 9. In the
charge/discharge process of the panel capacitor 9, the first and
third switches 1a and 1b turn on or off a connection between the
panel capacitor 9 and the power supply source Vcc. The second and
the fourth switches 3a and 3b turn on or off a connection between
the panel capacitor 9 and the ground (i.e., the X and Y
electrodes).
[0034] According to an embodiment of the invention, the switches
1a, 1b, 3a and 3b are field effect transistors (FETs), and a diode
is separately connected to each FET. As each switch 1a, 1b, 3a and
3b is turned on or off, a discharge sustain pulse as shown in FIGS.
3A and 3B (to be described later) is generated and supplied to the
panel capacitor 9. However, it is understood that other types of
switches are possible.
[0035] According to the present invention, a coil 7 is used as an
inductor to recover the reactive power. The coil 7 is connected in
series to one end of the panel capacitor 9 and is connected to a
junction point of the power supply source and the ground. At the
period of discharge, when the panel capacitor 9 is connected to the
ground, the coil 7 is charged with a discharge current flowing from
the panel capacitor 9. Thus, the coil 7 recovers energy and is able
to later charge the panel capacitor 9 with the recovered energy.
That is, if an electric charge of the panel capacitor 9 is
completely discharged, the energy charged in the coil 7 applies a
reverse voltage to the panel capacitor 9. The energy charged in the
coil 7 is transmitted to the panel capacitor 9, thereby recovering
the energy. The discharge sustain pulse is supplied to the
X-electrode thus uses the energy recovered by the coil 7 and
transmitted to the panel capacitor 9.
[0036] FIGS. 2A and 2B show electric current flows when the panel
capacitor 9 is charged/discharged by the Y-electrode unit driving
cell 1, and FIGS. 3A and 3B show a voltage wave shape indicating
each voltage at both ends of the panel capacitor 9 at the period of
charge/discharge thereof. Hereinafter, the charge/discharge
processes of the capacitor 9 will be described with reference to
FIGS. 3A and 3B, focusing the Y-electrode unit driving cell 1 by
way of example.
[0037] If the first switch 1 a is turned on, an electric current is
supplied from the power supply source Vcc and the panel capacitor 9
is charged with a voltage (during the period of t0.about.t2 of
FIGS. 3A and 3B). If the second switch 3a is then turned on to
charge the panel capacitor 9, an electric charge with which the
panel capacitor 9 is charged is discharged through the ground,
after bypassing the coil 7 as shown in FIG. 2A. At this time, the
coil 7 is charged with a magnetic energy by a discharge current
generated at the period of discharging the panel capacitor 9, and
the voltage of the panel capacitor 9 is completely discharged
(during the period of t2.about.t3 of FIGS. 3A and 3B). If the
electric charge of the panel capacitor 9 is entirely discharged, a
reverse voltage is applied to the panel capacitor 9 by the magnetic
energy charged in the coil 7. And, if the magnetic energy is
transmitted from the coil 7 to the panel capacitor 9, a somewhat
lower voltage than the initial voltage is applied to the panel
capacitor 9 and has a polarity opposite to the initial polarity
(during the period of t3.about.t4 of FIGS. 3A and 3B). At this
time, the controller (not shown), which generates control signals
to selectively switch each switch 1a, 3a, 1b, 3b on or off, turns
on the second switch 3a and the third switch 1b so as to supply a
voltage to the panel capacitor 9 from the power supply source Vcc,
thereby supplementing insufficient voltage of the panel capacitor 9
as shown in FIG. 2B (during the period of t4 of FIGS. 3A and
3B).
[0038] FIGS. 2C and 2D show electric current flows at the period of
charge/discharge of the panel capacitor 9 by the X-electrode unit
driving cell 3. The charge/discharge at the X-electrode unit
driving cell 3 are performed through the same operating processes
as of the Y-electrode unit driving cell 1. In the circuit of FIG.
2C, the voltage charged in the panel capacitor 9 is discharged when
the fourth switch 3b is turned on (during the period of t5.about.t6
of FIGS. 3A and 3B). During the discharge of the panel capacitor 9,
an electric current flows into the coil 7 and the coil 7 is charged
with the magnetic energy. If the panel capacitor 9 is completely
discharged, a reverse voltage is applied to the panel capacitor 9
by the magnetic energy charged in the coil 7. If the energy is
transmitted to the panel capacitor 9 from the coil 7 by the reverse
voltage applied to the panel capacitor 9, a somewhat lower voltage
than the initial voltage is applied to the panel capacitor 9 with a
polarity opposite to the initial polarity (during the period of
t6.about.t7 of FIGS. 3A and 3B). Here, the controller turns on the
first and fourth switches 1a and 3b to supply a voltage to the
panel capacitor 9 from the power supply source Vcc, thereby
supplementing insufficient voltage of the panel capacitor 9 as
shown in FIG. 2D (during the period of t7 of FIGS. 3A and 3B).
[0039] In this way, if sustain pulses are alternately supplied to
the X-electrode and the Y-electrode by charging/discharging the
panel capacitor 9, the discharge is sustained in the discharge
sustaining electrode pair. With this configuration, the reactive
power recovering circuit recovers discharged voltages at the period
of charge/discharge of the panel capacitor and is simplified in
structure. In addition, since the number of switching devices of
the reactive power recovering circuit is reduced, power consumption
is reduced.
[0040] FIG. 5 shows an AC type plasma display panel 10 using the
reactive power recovering circuit according to an embodiment of the
invention. The plasma display panel 10 has a front substrate 11 and
a rear substrate 12 opposed to and facing each other. Strip-shaped
common electrodes 13 and strip-shaped scan electrodes 14 (X and Y
electrodes 13, 14) are alternately formed on a bottom surface of
the front substrate 11. A bus electrode 15, which reduces the line
resistance, is formed on a bottom surface of each of the common and
scan electrodes 13 and 14. A first dielectric layer 16 is formed on
a bottom surface of the front substrate 11 to cover the common
electrodes 13, the scan electrodes 14, and the bus electrodes 15. A
protective layer 17, such as a magnesium oxide (MgO), is formed on
a bottom surface of the first dielectric layer 16.
[0041] Strip-shaped address electrodes 18 are formed on a top
surface of the rear substrate 12 to be perpendicular with the
common and scan electrodes 13 and 14. The address electrodes 18 are
covered by a second dielectric layer 19. Strip-shaped partitions
100 are formed on the second dielectric layer 19 parallel with the
address electrodes 18. Red (R), green (G) and blue (B) phosphor
layers 110 are formed on the inner walls of the partitions 100.
[0042] As described above, according to the present invention,
there are provided a plasma display panel equipped with a reactive
power recovering circuit simplified in structure and a method of
controlling the same. Further, since the number of parts of the
reactive power recovering circuit is reduced, power consumption is
accordingly reduced.
[0043] Although the embodiments of the present invention have been
disclosed for illustrative purposes, those skilled in the art will
appreciate that various modifications, additions and substitutions
are possible, without departing from the scope and spirit of the
invention as disclosed in the accompanying claims and equivalents
thereof.
* * * * *